نتایج جستجو برای: steppe rangelands

تعداد نتایج: 6506  

2010
Kirk W. Davies Jonathan D. Bates Tony J. Svejcar Chad S. Boyd

Livestock grazing potentially has substantial influence on fuel characteristics in rangelands around the globe. However, information quantifying the impacts of grazing on rangeland fuel characteristics is limited, and the effects of grazing on fuels are important because fuel characteristics are one of the primary factors determining risk, severity, continuity, and size of wildfires. We investi...

Journal: :international journal of advanced biological and biomedical research 0
pejman tahmasebi kohyani assistant professor,department of range and watershed mangement,faculty of natural resource and earth science, shahrekord university, po. box 115, shahrekord, iran yousef askari ph.d student of forestry, faculty of natural resources and earth science, university of shahrekord, shahrekord, iran

semi-steppe rangelands are a complex, highly dynamic and often multi-layered mosaic of grassland, shrubland, and intermediate communities. a few recent studies have explicitly or implicitly developed synthetic hypotheses about how interactive effects of human made disturbances initiate dynamic changes in plant community composition to cause a shifting mosaic of vegetation pattern across the lan...

2008
Keith T. Weber Steven S. Seefeldt

The potential for high severity fires to affect changes in rangelands is considerable, and for this reason, assessing fire severity is critical. We explored fire severity modeling in rangelands by applying post-fire field observations to Satellite Pour l'Observation de la Terre 5 (SPOT 5) imagery using Classification Tree Analysis (CTA) techniques at two 2005 burns. The results of these analyse...

Pejman tahmasebi Kohyani, Yousef askari

Semi-steppe rangelands are a complex, highly dynamic and often multi-layered mosaic of grassland, shrubland, and intermediate communities. A few recent studies have explicitly or implicitly developed synthetic hypotheses about how interactive effects of human made disturbances initiate dynamic changes in plant community composition to cause a shifting mosaic of vegetation pattern across the lan...

Pejman tahmasebi Kohyani, Yousef askari

Semi-steppe rangelands are a complex, highly dynamic and often multi-layered mosaic of grassland, shrubland, and intermediate communities. A few recent studies have explicitly or implicitly developed synthetic hypotheses about how interactive effects of human made disturbances initiate dynamic changes in plant community composition to cause a shifting mosaic of vegetation pattern across the lan...

2010

For most ecosystems, net ecosystem exchange of CO2 (NEE) varies within and among years in response to environmental change. We analyzed measurements of CO2 exchange from eight native rangeland ecosystems in the western United States (58 site-years of data) in order to determine the contributions of photosynthetic and respiratory (physiological) components of CO2 exchange to environmentally caus...

Journal: :Environmental management 2011
Dustin D Johnson Kirk W Davies Peter T Schreder Anna-Marie Chamberlain

Medusahead (Taeniatherum caput-medusae (L.) Nevski) is an exotic annual grass invading rangelands in the western United States. Medusahead is a serious management concern because it decreases biodiversity, reduces livestock forage production, and degrades the ecological function of rangelands. Despite the obvious importance of ranchers as partners in preventing and managing medusahead in rangel...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید